Mia Grace, who weighed in at in at 7 pounds, 12 ounces, at birth, is the queen's fourth great-grandchild, the 16th in line to the British throne and will hold no royal title. She'll go by Miss Tindall, according to the BBC. But around these parts she'll be affectionately called "Prince George's little cousin."

Phillips, who goes by Mrs. Michael Tindall, is expected to share a photo of the newest royal in the next few days, according to People.

Following Mia's birth, Tindall took to Twitter to update his followers about his growing family and fatherhood.

"Thanks so much for all your kind messages," he tweeted. "Definitely the best day of my life today, so happy.! The girls are both doing great!" Days later, he indicated that he was perfecting the "one handed nappy change."

The couple reportedly took their time coming up with a name because they chose not to learn the baby's gender until she was born, the Daily Mail reported.

The first-time mom, an Olympic equestrian and silver medalist, married Tindall in July 2011 at Canongate Kirk in Edinburgh, just months after Prince William and the former Kate Middleton's globally watched royal wedding.